i went to the dyno last week to find out my a/f ratio was 14.1:1. so i picked up a afpr and i was wondering how much pressure i could increase it to be at around 12.8-13.1 without having to go back to the dyno. is there any way to estimate. a have the afpr and fp gauge. any opinions are greatly appriciated, thanks.

 

I think the only other real way is to raise the pressure a bit and go do a few tests on the butt o meter. Other than that there really won't be a way to tell without a a/f guage.

 

or is there any scale, like this much of a pressure increase will change your a/f this much?

 

That's all in the tuning man. If you increase the fuel pressure, the computer will adjust the injector pulse width to get back to it's programmed target A/F ratio. If your fuel pressure is stable I wouldn't bother with an adjustable fuel pressure regulator. FWIW, I just replaced my adjustable regulator with a stock one and the car runs 200% better.

 

i have a speed density car, the computer will not re-adjust itself. thats why people see big gains with these on 93's. still need an answer by the way. thanks